Loss of taste/smell, stomach upset, headache may predict COVID in kids
A study of SARS-CoV-2–positive Canadian children in CMAJ yesterday showed that 64.1% of children were symptomatic, with loss of taste or smell, stomach upset, headache, and fever most predictive of infection.
Researchers analyzed reverse-transcriptase polymerase chain reaction (RT-PCR) results and self-reported symptoms for children who tested positive for SARS-CoV-2 in Alberta from Apr 13 to Sep 30. Of 2,463 children tested, 1,987 had a positive result, with fever (25.5%), cough (24.5%), and runny nose (19.3%) the most commonly reported symptoms in infected patients.
Cough and runny nose were also common in SARS-CoV-2–negative patients and were not predictive of a positive result; neither were sore throat, nasal congestion, or diarrhea.
Loss of taste or smell, however, was highly predictive, with a likelihood of test positivity more than seven times higher than that for patients without this symptom (positive likelihood ratio [LR], 7.33, 95% confidence interval [CI], 3.03 to 17.76). Other symptoms predictive of a positive result included nausea and vomiting, headache, sneezing, and fever (LR values ranging from 1.68 to 5.51).
When the researchers combined loss of taste/smell, nausea/vomiting, and headache symptoms, the overall likelihood was highly predictive of a positive result (LR, 65.92; 95% CI, 49.48 to 91.92), but the infrequency of loss of taste/smell in children may limit its predictive value.
"Administrators of screening questionnaires for schools or daycares may wish to consider reassessing the symptoms they screen for to include only those that are most strongly associated with positive results for swabs for SARS-CoV-2 infection," the authors advise.
"Because more than one-third of pediatric patients who test positive for SARS-CoV-2 infection exhibit no symptoms, identifying children who are likely to be infected is challenging," said lead author Finlay McAlister, MD, MSc, in a Canada Hospital News press release.
As a result of that, Canadian hospital experts caution in an accompanying commentary, that symptom screening is unlikely to prevent every infected child from entering school. "School-based health and safety measures beyond screening—including physical distancing, hand hygiene, masking, improved ventilation and outdoor learning opportunities—play an essential role in preventing the spread of infection," they note.
Nov 24 CMAJ study
Nov 24 CMAJ commentary
Nov 24 Canada Hospital News news release
Chilblains skin lesions noted in some COVID-19 patients
A French study in JAMA Dermatology today found chilblains-like skin lesions in COVID-19 patients, suggesting a heightened virus-induced immune response associated with SARS-CoV-2 infection.
Chilblains—shiny, bluish-red discolorations of the skin caused by inflammation of small blood vessels—typically occur on fingers and toes, are often accompanied by burning and itching sensations, and can lead to blisters, skin ulcers, infection, and occasionally necrosis—tissue death.
The study authors identified 40 outpatients suspected of having COVID-19 who presented with chilblains at Nice University Hospital from Apr 9 to Apr 17. Chilblains occurrence is unusual in temperate areas, and the incidence corresponded with the spread of SARS-CoV-2 in the region.
None of the chilblains patients tested positive for SARS-CoV-2 via RT-PCR, but 60% had contact with possible COVID-19 cases, and 11% met the definition for a possible COVID-19 infection in the 6 weeks before developing chilblains. Despite negative RT-PCR tests and the lack of a clear causative link between infection and chilblains, 30% of patients tested positive for SARS-CoV-2 antibodies.
Most of the patients were otherwise healthy adolescents and young adults. Symptoms resolved in all patients, but some experienced slow recovery—35% still had cold or discolored toes at 1-month follow-up.
Laboratory findings in chilblains patients showed elevated levels of type I interferon alpha (IFN-α), which are a class of cytokines, or immune proteins, that act to inhibit virus replication and are crucial in the early response to viral infections. IFN-α production is higher in young people and decreases with age, and previous studies have shown an association between severe COVID-19 in older populations and a defective IFN-α response.
"The exaggerated type I interferon response might also explain the relatively low rate of seropositivity in patients with chilblains because those patients could clear SARS-CoV-2 infection before humoral immunity occurs," the authors wrote.
Nov 25 JAMA Dermatol study